Companies House Accounts Filed \u2014 Do I Still Need to File the CT600?
Yes — filing accounts at Companies House and filing your CT600 with HMRC are two completely separate obligations with different deadlines. Completing one does not satisfy the other.
Two Separate Obligations
| Obligation | Goes to | Deadline | What is filed |
|---|---|---|---|
| Company accounts | Companies House | 9 months after year end | Balance sheet (and optionally P&L) |
| Corporation Tax return (CT600) | HMRC | 12 months after year end | CT600 form + accounts + computations |
- Company accounts → Companies House: due 31 July 2026
- CT600 → HMRC: due 31 October 2026
Do Small Companies Need to File the P&L at Companies House?
No. Small and micro-entity companies are exempt from including the profit and loss account in their public filing at Companies House. Filing the balance sheet only is correct and meets the Companies House requirement.
Your P&L figures do go to HMRC as part of the CT600 package (TinyTax includes them automatically in iXBRL format) — but they are not placed on the public register.
Does a Trading Loss Affect My Filing Obligations?
No. If your company made a trading loss, there is no corporation tax to pay — but you are still required to file the CT600 with HMRC by the 12-month deadline. The return declares the loss (which HMRC may allow you to carry forward against future profits) and confirms that no tax is owed.
Corporation tax is ordinarily payable 9 months and 1 day after the year end. If the company made a loss, nothing is owed on that date either.
Why Does HMRC Say I Need "Professional Software"?
HMRC retired its own free online CT600 filing service for most companies. You now need to use HMRC-approved third-party software to file online. TinyTax is exactly that software — it prepares and submits your CT600, tax computation, and iXBRL accounts directly to HMRC.
You can build and preview your entire return for free on your TinyTax dashboard and only pay when you are ready to submit.
Common Questions
I already filed the balance sheet at Companies House — is my accounting obligation done?
For Companies House, yes — as long as your accounts covered the correct period and were filed before the deadline.
For HMRC, no — the CT600 is still outstanding and must be filed by 12 months after the year end.
Do I need to submit the P&L separately to anyone?
No. Your P&L is not filed publicly at Companies House (small company exemption). TinyTax includes it automatically in the iXBRL accounts sent to HMRC as part of the CT600 submission.
Can I file the CT600 even if I made a loss?
Yes, and you must. A trading loss still requires a CT600. Enter your income and expenditure figures and TinyTax will calculate the nil tax liability and declare the loss to HMRC.
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